Router losing steps. Solution needed. Will this help?

[cncbobuk]

This needs explaining better.? Do you mean your just using 1 Step and 1 Dir signal to drive borh drives.?

Sorry I probably didn't make this clear. Y axis has one motor at each end of the gantry each driving their own rack. Each motor has it's own MA860H driver but the pulse and direction inputs are connected to the same output from the controller.

Regards the R&P setup then what size are the pinions, ie diameter not No teeth.?
Reason I ask is because from the 0.01042 per step then that translates to 16.672 pitch with 1600MS and with a 5:1 ratio this means a pinion diameter of approx 83.5mm and this means a small pinion size.!
With Module size then pinion size for same number of teeth increases which means your module size would need to be small to have diameter of only 83mm And I'd be surprised if it's less than module 1 and more likely to be Mod 1.5 or even imperial.? . . . All this makes me wonder if your actually set correctly.?

I assume you mean 83mm circumference??? if so you are correct, the pinion diameter is approximately 26mm I can only conclude the basic setup is right as when I do a simple full depth cut the produced dimensions are essentially correct.

Regards USB then I'd steer clear of using USB to power the BOB as it's unreliable and if it as the option to use external power then do so.

The board does have external 12-36v supply connection, it connects to Mach 3 via USB not parallel port.

If you want the Best Motion control card for Mach3 then look at the Cslabs Csmio-IP-M or IP-S products which blow the others away. They also have Spindle speed control built into them. DONT use BOB so take away the biggest hassle in any control box and provide 24V I/O which connects directly to the Unit thru nice DIN rail mounted connectors so very neat and industry standard.

I'll check them out, cheers.